| 摘要 |
PURPOSE:To obtain the titled foam which is soft even without any plasticizer added and free of coloration and has uniform fine closed cells and excellent heat insulating properties, by expanding a graft copolymer of a specified ethylene- vinyl acetate copolymer and vinyl chloride. CONSTITUTION:100pts.wt. ethylene-vinyl acetate copolymer (A) with a MI of 1- 500g/10min, containing 5-60wt% vinyl acetate, is introduced into 5-100pts.wt. vinyl chloride or its mixture with another monomer (B), allowing component A to swell without being dissolved, followed by graft polymerizing thereof at 30- 80 deg.C in an aqueous solvent to obtain a vinyl chloride resin. Then, 100pts.wt. said resin, 1-50pts.wt. foaming agent (e.g. azodicarbonamide), 0.2-3.0pts.wt. organic peroxide (e.g. dicumyl peroxide), not more than 20pts.wt. stabilizer (e.g. tribasic lead sulphate), etc. are mixed, and heated under pressure to be foamed by a press foaming process, etc.
|
